To investigated the effect of a hyperoncotic CPB-prime with hydroxyethyl starch (HES) 6% (130/0.4) on extravascular lung water (EVLW) and post-pump cardiac and pulmonary functions. This study plan approved by the hospital ethics committee review. In 40 randomized patients undergoing elective coronary artery bypass graft surgery (CABG), a colloid prime (COP:42.5 mmHg, HES-group, n = 20) and a crystalloid prime (Ringer's lactate, crystalloid group, n = 20) of equal volume were compared with respect to the effects on cardiopulmonary function. Cardiac index (CI), mean arterial pressure (MAP), pulmonary capillary wedge pressure (PCWP), systemic vascular resistance index (SVRI), pulmonary artery pressure (PAP), pulmonary vascular resistance index (PVRI), alveolo-arterial oxygen difference (AaDO2), pulmonary shunt fraction (Qs/QT), extravascular lung water (EVLW), COP, fluid balance and body weight were evaluated peri-operatively. Pre-operative demographic and clinical data, CPB-time, crossclamp time and the number of anastomoses were comparable for both groups. During CPB, COP was reduced by 22% in the HES-group [(16.7 ± 3.9) vs (21.5 ± 2.2) mmHg, P < 0.05] while it was reduced by more than 50% of the pre-CPB value [10.7 ± 2.0 vs (22.7 ± 1.9) mmHg, P < 0.05] in the crystalloid group (P < 0.05 HES-group vs. crystalloid group). Post-CPB EVLW was unchanged in the HES-group but it was elevated by 21% in the crystalloid group (P < 0.05 HES-group vs crystalloid group), CI was higher in the HES-group [(3.3 ± 0.3) vs (2.7 ± 0.7) L/min, P < 0.05]. Fluid balance was less in the HES-group (715 ± 544 vs 1 951 ± 487, P < 0.05). Post-operative weight gain could be prevented in the HES-group but not in the crystalloid group (1.4 ± 1.1 vs -0.3 ± 1.3, P < 0.05). No significant differences were seen for MAP, PAP, PCWP, SVRI, PVRI, AaDO2 and (Qs/QT) between the two groups at any time. Hyperoncotic CPB-prime using HES 6% improves CI and prevents EVLW accumulation in the early post-pump period, while pulmonary function is unchanged.
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